Article sorting system controlled by radio frequency energy signals



July, 1910 Arron/5K5 United States Patent Oflice 3,520,406 ARTICLESORTING SYSTEM CONTROLLED BY RADIO FREQUENCY ENERGY SIGNALS John CharlesTurner, Danville, Calif., assignor to Spott Electrical Company, Hayward,Calif., a corporation of California Filed May 13, 1968, Ser. No. 728,521Int. Cl. B07c /34 US. Cl. 209-111.5 2 Claims ABSTRACT OF THE DISCLOSUREAn article-handling system for processing passenger baggage at airlineterminals. A particular form of the system includes a conveyor havingboth a collection section along which baggage is accumulated and adistribution section providing a plurality of distribution branches orstations respectively corresponding to particular flight destinationsand into which baggage is selectively diverted in accordance with thedestinations thereof. A plurality of diverters disposed in respectiveassociation with the distribution branches are operative selectively toefiect diversion thereinto of individual pieces of baggage beingadvanced along the conveyor. Each piece of baggage carries a tagequipped with a self-identifying responder providing control indiciacorresponding to the destination indicated by the tag; and a pluralityof interrogation units respectively associated with the diverters areoperative to transmit interrogation signals for interception by theresponders. Whenever control indicia of a predetermined characteranswers an interrogation signal, the interrogation unit responsivethereto operates the associated diverter to segregate or divert thepiece of baggage carrying such answering responder into the appropriatebranch.

This invention relates to an article-handling system in whichintermingled articles are distributed in accordance with certainpredetermined characteristics so as to collect or group those articleshaving like characteristics. The invention relates more particularly toa system of this type in which the articles themselves by means ofselfidentification determine and control such distribution andcollection thereof. The system has utility in a variety of environments,and a specific instance thereof is baggage handling and especially thecollection and distribution of baggage in airline terminals.

Considering the processing of airline baggage as typifying a use of theinvention, it may be noted that the problems of tagging the baggage ofdeparting passengers, collecting or accumulating the baggage from thevarious check-in counters, and then routing the baggage to stations fromwhich it is finally placed aboard the proper planes to carry it to itsdestination are becoming more and more intense because of the increasingnumber of individual flights and the increasing number of passengerscarried by each aircraft-several hundred passengers being anticipatedfor the newest jet planes. The same general problems pertain todistribution of the baggage of deplaning passengers, and the presentcomplexities in this respect will be aggravated by the large masses ofpassengers deplaning from such newer planes.

The ditficulties inherent in the processing of such baggage is moreevident when it is appreciated that at present each piece of baggage iscompletely dormant or inactive, unable to cooperate in reaching itsdestination (as do airline passengers) except to carry a tag that mustbe manually inspected at each position along the baggage route at whicha change in direction or other selection might be made in routing thebaggage toward its destination. Any such change in direction alsorequires manual attention,

3,520,406 Patented July 14, 1970 and not only does all this requirementfor manual attention prove costly, but error in misdirection due tohuman omissions and vagaries occurs at an increasing rate.

In view of the foregoing, it is evident that it would be advantageous tohave an improved system for handling baggage at airline terminals, andespecially a system in which each individual piece of baggage could takean active part in determining the routing therefor necessary to reachits proper destination without the requirement for human intervention;and it is, accordingly, an object of the present invention to providesuch an improved system. Another object of the present invention is inthe provision of an improved article-handling system in whichintermingled articles, respectively equipped with selfidentifyingresponders providing control indicia corresponding to certainpredetermined characteristics of the articles, are distributed inaccordance with such characteristics in response to the control indiciaprovided by the responders in answer to interrogation signals directedthereto. Additional objects and advantages of the invention will becomeapparent hereinafter as the specification develops.

An article-handling system embodying the invention includes a conveyorhaving a collection section along which articles are accumulated in anintermingled manner unrelated to any group-determining characteristicsthereof. The conveyor also has a distribution section providing aplurality of distribution branches or stations respectivelycorresponding to certain characteristics (flight destinations, forexample) by which the articles are to be collected or grouped. Aplurality of diverters disposed in respective association with thedistribution branches are operative selectively to effect diversion intothe branches of individual articles being advanced along the conveyor.Each such article is equipped With a selfidentifying responder providingcontrol indicia corresponding to a particular characteristic by whichthe article is to be grouped; and a plurality of interrogation unitsrespectively associated with the diverters are operative to interrogatethe articles as they are advanced by the conveyor. Whenever controlindicia of a predetermined character answers an interrogation signal,the interrogation unit responsive thereto actuates the associateddiverter causing it to segregate or divert the article equipped with theanswering responder into the appropriate distribution branch of theconveyor.

An embodiment of the invention is illustrated in the accompanyingdrawing, in which:

FIG. 1 is a diagrammatic view of an article-handling system embodyingthe invention; and

FIG. 2 is a broken perspective view illustrating one of the diverters ofthe system in association with an interrogation unit.

The particular articles-handling system illustrated in FIG. 1 isintended for use at an airline terminal to process the baggage ofdeparting passengers. The system includes a conveyor 10 comprising acollection section 11 and a distribution section 12. The collectionsection 11 has a plurality of supply branches 13, 14 and 15 feedingthereinto, and such branch conveyors may be located at quite divergentor separated positions throughout the terminal as, for example, theparking garage thereof, street entrance to the terminal, and each of theticket counters therewithin. It will be appreciated that any convenientnumber of branch infeed or supply conveyors can be provided each leadingeither directly or indirectly to the main line of the collection section11. As will be brought out more clearly hereinafter, each piece ofbaggage is tagged before being delivered to the collection section 11 ofthe conveyor, and tagging stations 16, 17

and 18 are shown in respective association with the branch infeedconveyors.

The distribution section 12 of the conveyor has a plurality ofdistribution branches or stations located therealong respectivelyrepresentative of particular characteristics by means of which thearticles are to be distributed or grouped. In the case of thebaggage-handling system illustrated, the distribution branches representdifferent flights or trip destinations for the baggage, and from suchbranches the pieces of baggage grouped or collected therealong will beplaced upon proper aircraft for transport thereby to the appropriatedestination. In the particular system shown, there are ten suchdistribution branches respectively denoted with the numerals 19 through28; and a further branch or collection station at the end of thedistribution section 12 is also provided so as to collect as a groupbaggage which has not been diverted into one of the branches 19 through28.

A plurality of diverters are disposed along the distribution section 12in respective association with the branches 19 through 28 so as toselectively divert articles of baggage thereinto. Accordingly, there areten such diverters in the particular baggage-handling systemillustrated, and they are respectively denoted with the numerals 30through 39 and are associated with the branches 19 through 28,respectively. A continuously operative diverter or turn section 40 isprovided in association with the branch 29 so as to divert thereinto allarticles of baggage not diverted into one of the branches 19 through 28.A plurality of interrogation units are respectively associated with thediverters 30 through 39, and such interrogation units are respectivelydenoted with the numerals 41 through 50.

The interrogation units are each operative to transmit an interrogationsignal across the distribution section 12 of the conveyor so as to beintercepted by the articles of baggage being advanced therealong. Aswill be explained hereinafter, the interrogation units control operationof the respectively associated diverters and, in this respect, each unitactuates its diverter to cause the same to divert into the associatedbranch conduit each article of baggage that responds in a predeterminedmanner to the interrogation signals transmitted by the associated unit.It may be observed that the interrogation signals directed across thedistribution section 12 of the conveyor are oriented so as to beintercepted by each piece of baggage just prior to its reaching thediverter associated with the particular interrogation unit so thatadequate time is afforded for the interrogation unit to actuate thediverter and thereby cause it to segregate into the associateddistribution branch each piece of baggage responding in a predeterminedmanner to the interrogation signal intercepted thereby.

Evidently, since there is no particular order to the manner in whichbaggage is fed to the collection section 11 and, therefore, no assuranceof spacing between successive articles being advanced therealong, it isadvantageous to provide some minimum spacing between successive articlesalong the distribution section 12 so as to afford sufficient time foreach interrogation unit and diverter associated therewith to eitherdivert or pass one article and be reconditioned for interception of thenext successive article advanced thereto. Such separation betweensuccessive articles may be provided by having the distribution section12 function at a higher linear velocity than that of the collectionsection 11; and by way of example, the collection section might have alinear velocity of the order of 100 feet per minute and the distributionsection 12 a linear velocity of the order of 200 feet per minute. Itwill be apparent that the diverters are necessarily operative toaccommodate articles at the rate or velocity at which they are advancedby the distribution sceion 12, and the interrogation units may belocated with respect to the diverters so as to afford any lead time thatmay be required for their actuation.

A typical diverter is illustrated in FIG. 2, and for purposes a specificidentification may be taken to be the aforementioned diverter 30. Itshould be noted, however, that each of the diverters 30 through 39 maybe identical and, correspondingly, the interrogation units 41 through 50may all be identical except for the particular interrogation signalsrespectively transmitted thereby.

The diverter 30 may be completely conventional and can be any one of anumber of selective transfers such as the Automatic Diverter Transfersold by the Stewart- Galpat Corporation of Zanesville, Ohio.Accordingly, and as shown in FIG. 2, the diverter 30 has a somewhat T-shape with the stem 51 thereof communicating with the distributionbranch 19 so as to deliver articles thereto and the crossbar 52communicating at each end thereof with the main line of the distributionsection 12. The crossbar 52 comprises a plurality of spaced apartconveyor belts 53 continuously driven by a motor and drive train 54 sothat the belts 53 travel from left to right along the upper stretchesthereof. as viewed in FIG. 2.

Aligned with the stem 51 and defining the junction thereof with thecrossbar 52 are a plurality of rollers 55 that are adapted to bepositively driven and are alternately disposed between the spaced apartbelts 53 and are selectively movable between a lower position in whichthey are positioned below the belts so as not to interfere with articlesof baggage being advanced thereby, and the elevated position illustratedin FIG. 2 in which they project above the belts 53 and are thereforeoperative to engage such article of baggage and divert the same frommovement along the bar 52 and main line of the conveyor section 12 intothe stem 51 of the diverter and onto the associated distribution branch19. The diverter rollers 55 are selectively movable between the lower,retracted and upper, operative positions thereof by mechanism providedfor this purpose which is responsive to external command such asprovided by a control switch. Since the diverter 30 is conventional, nofurther details concerning its construction and operation appearnecessary.

Associated with the diverter 30 is the aforementioned interrogation unit41 which is contained within a casing supported above the diverter 30adjacent the entrance thereto by a support structure in the form of anL-shaped bracket 56 bolted or otherwise secured to the casing of theunit 41 and fixedly secured to the side wall structure 57 of thediverter. As indicated hereinbefore, all of the interrogation units 41through 50 may be identical except for the particular interrogationsignals respectively provided thereby and, for example, such unit mightbe a Sensormatic Detector commercially available from The JKRCorporation of Akron, Ohio. The details of such unit are set forth inUS. Pat. No. 2,774,060, to which reference may be made for such details.

Interrogation units of this type in effect transmit or supplyinterrogation signals having a predetermined frequency usually in themegacycle range and often in the range of from 300 to 5,000 megacycles.In the particular system shown in FIG. 1, the interrogation units 41through 50 will transmit interrogation signals having differentfrequencies as, for example, frequencies differing from each other insteps of megacycles although the particular frequencies employed are notcritical. It may be observed that in a baggage-handling system forairline terminals, it may be convenient or desirable to change from timeto time the flight destinations represented by one or more of thedistribution branches 19 through 28; and such change is mostexpeditiously accomplished by changing the frequency of theinterrogation signal transmitted by the associated interrogation unit.This could be done either by interchanging interrogation units in thosecases in which the units are non-adjustable or by selectively varyingthe frequency when multiple-frequency units are provided. In any event,the interrogation units are constructed and arranged so that when aresponse of a predetermined character is sensed in answer to theinterrogation signals transmitted thereby, the unit actuates the controlswitch for the associated diverter to elevate the rollers 55 thereof andthereby divert the responding article to the distribution branchconnected with such diverter. Each interrogation unit includes a relayor solenoid that is energized in response to the sensing of an answeringsignal of predetermined character; and accordingly, to interconnect theunit 41 with the diverter 30, it is only necessary to provide aconventional interconrection between such relay or solenoid and thecontrol switch of the diverter.

Each article of baggage being advanced by the distribution conveyor 12is equipped with a responder adapted to provide control indiciacorresponding to the destination of the article, and this is mostconveniently provided by incorporating such responder in the tagscustomarily attached to each article of baggage and which also designateby visual identification the destination intended for the article. Thusin FIG. 2, a typical article of baggage 58 is shown advancing along theconveyor section 12 toward the diverter 30, and it carries a tag 59having incorporated therein a responder providing a control indiciawhich may be sensed by one of the interrogation units 41 through 50. Theparticular form of responder will depend upon the character of theinterrogation unit employed; and in the event of the interrogation unitsbeing of the type disclosed in the aforementioned US. Pat. No.2,774,060, the responder may be a tuned or resonant circuit and can takethe form of an electric conductor of predetermined length printed ontothe tag 59. Again, for details concerning such responder, reference maybe made to the disclosure comprised by the issued patent.

By way of example, if the distribution branch 19 is intended to collectarticles of baggage thereon having say Chicago for a destination, all ofthe articles of baggage intended for Chicago will carry a tag 59corresponding to such destination and such tags will have been placedupon the article at one of the stations 16 through 18 in the usualmanner. The tag 59 will, therefore, contain a responder providingcontrol indicia of predetermined character which, for example, might bea resonant circuit tuned to a frequency of 300 megacycles.Correspondingly, the interrogation unit 41 would continuously transmitsignals at such frequency of 300 megacycles. When each Chicago-boundarticle 58 is advanced by the distribution section 12 into the range ofthe signals transmitted by the unit 41 so as to intercept such signals,the consequent change in load on the circuitry within the unit 41 issensed thereby so as to energize the associated relay or solenoid andthereby elevate the rollers 55 to divert such responding article ofbaggage onto the distribution branch 19.

Each of the interrogation units and diverter associated therewith willfunction in exactly the same manner to divert each article of baggagecarrying a responder-equipped tag providing control indiciacorresponding to the flight destination represented by the interrogationunit, diverter and distribution branch associated therewith. As statedhereinbefore, the flight destinations represented by any distributionbranch can be changed by shifting the frequency of the interrogationsignals provided by the associated interrogation unit to a frequencydescriptive of a different flight destination or by interchangingdiverters, as the case may be. The distribution branch 29 andcontinuously operative diverter or turn unit 40' associated therewithare provided to collect any articles of baggage that may fail to carry asuitable baggage tag, that for some reason might fail to be sensed bythe appropriate interrogation unit therefor, which might be intended forflights leaving at some future date, etc., and must be manuallyinspected and directed to the appropriate locations therefor.

The described baggage-handling system requires the use of no carts orother carriers for the individual pieces of baggage because no specialorientation of the articles is required in order to be sensed by theappropriate interrogation units. The system lends itself to passengertagging of the baggage since it is only necessary to select a tag forthe proper destination and attach it to the article of baggage in anymanner since, as stated, precise positioning of the article of baggageor the tag thereon is not essential. In a physical sense, thedistribution section 12 could extend along a tunnel or passagewayunderlying the Walkways from the main terminal building to the variousloading stations, and the distribution branches could extend directly tothe service area associated with the loading stations. All of theconveyor mechanisms may be completely conventional and can be of thetype now in use to transport baggage from one location to another at anairline terminal. In such event, the conveyor mechanisms ordinarily willcomprise endless belts which are more suitable to handling odd-shapedpieces of baggage than are roller-type conveyors.

The system is applicable to the handling and distribution of articlesand materials generally as well as for processing baggage at airlineterminals and, for example, the distribution of parts and components invarious manufacturing plants (an automobile assembly line, for example)is another typical use. Also, various signal sensing or interrogationarrangements might be used in place of the signal transmitter andtuned-circuit responder described, as for example magnetic, light, andsound systems. In any event, the particular articles being processed areself-identifying, and therefore take an active part in selecting theroutes leading to their approximate destinations, and accomplish suchselection wholly without human intervention.

While in the foregoing specification an embodiment of the invention hasbeen set forth in considerable detail for purposes of making a completedisclosure thereof, it will be apparent to those skilled in the art thatnumerous changes may be made in such details without departing from thespirit and principles of the invention.

What is claimed is:

1. In an article-handling system in which intermingled articles areseparated by self-identification into a plurality of groups inaccordance with certain group-determining characteristics, a conveyorhaving a collection section adapted to receive articles and advance thesame in an intermingled succession thereof having no specific relationto their group-determining characteristics, a plurality of infeedbranches respectively connected with said collection section so as todeliver articles thereto, said conveyor having also a distributionsection for receiving such succession of intermingled articles from saidcollection section and being equipped with a plurality of distributionbranches defining a plurality of assembly stations respectivelycorresponding to such groups and being adapted to have articles divertedthereto, mechanism providing a velocity differential between saidconveyor sections with said distribution section having the greatervelocity so as to enforce a minimum spacing between substantially allsuccessive articles advanced along said distribution section, aplurality of diverters disposed along said distribution section inrespective association with said distribution branches and each beingselectively operative to divert articles into the associateddistribution branches, each of said diverters having transverselyoriented conveyor segments the first of which includes a plurality ofspaced apart endless belts disposed in substantial alignment with saiddistribution section and effectively comprising a portion thereof andthe second of which includes a plurality of power driven rollersinterposed between said belts in substantial alignment with theassociated distribution branch and selectively displaceable between aninoperative retracted position in which articles can be transportedthereover by said first conveyor segment and an extended position forintercepting an article advanced thereto to divert the same into theassociated distribution branch, means associated with each diverter forraising and lowering said second conveyor segment thereof between itsextended and retracted positions, guide structure disposed along saiddistribution section adjacent each of said distribution branches forguiding the movement of any article diverted thereinto, a plurality ofinterrogation units for interrogating such articles and beingrespectively associated with said diverters for controlling operation ofthe movable components thereof in response to control indicia suppliedby such articles, a plurality of inverted generally L-shaped supportstructures secured to said conveyor at spaced apart locations along saiddistribution section respectively adjacent said diverters and havingsubstantailly horizontal legs extending over said distribution sectionand respectively supporting said interrogation unit in spaced relationwith the path of movement of articles along said distribution section, aplurality of responders respectively carried by tags to be attached toarticles and respectively providing control indicia specificallydescriptive of the ground-determining characteristics of the particulararticle to which it is attached so as to acknowledge the interrogationof one particular interrogation unit and thereby cause it to actuate thediverter associated therewith to divert the responding articles into theassociated distribution branch and its assembly station, and anaccumulator station connected with said distribution section adjacentthe terminus thereof for receiving articles not diverted into one ofsaid distribution branches,

each of said interrogation units being operative to transmit radiofrequency signal information in the megacycle range for interception bythe successive articles along said distribution section, each of saidresponders comprising a circuit responsive to the frequency of aparticular interrogation unit so as to respond only to the signalinformation thereof, and the signal information transmitted by saidinterrogation units being separated one from another by steps of theorder of 100 megacycles.

2. The article-handling system of claim 1 characterized by being adaptedto handle baggage at an airline terminal, and in which the aforesaidgroup-determining characteristics are flight destinations for thebaggage articles.

References Cited UNITED STATES PATENTS 2,734,643 2/1956 MacRae 214-413,260,349 7/1966 Vander Meer 19838 3,438,489 4/1969 Cambornac 209- 111.s

GERALD M. FORLENZA, Primary Examiner R. B. JOHNSON, Assistant ExaminerUS. Cl. X.R.

